Mercury fulminate and method of treating same



Patente'dilune 25, 1929,

' UNITED STAT PATENT @OFFICE.

JOSERB -D. MONUTT, OF NEW HAVEN, CONNECTICUT, ASSIGNOR, BY HESNE ASSIGN- MENTS, TO WINCHESTER REPEATING ARMS COMPANY, OF NEW HAVEN, CON- QI'FIOTIOUT, -A CORPORATION OF DELAWARE.

EROURY FULMINA TE AND METHOD OF TREATING SAME.

1Tb Drawing.

My invention relates to mercury fulminate and methods of treating the same.

The object of this invention is the production of mercury fulminate which will not 5 have any harmful effect on metal with which it comes in contact.

Mercury fulminate is used largely as a detonating agent in priming compounds ofammunition. As the mercury fulminate hereto- 1 fore used for this purpose contained free mercury in varying amounts, trouble has been experienced in the past due to the tendency of the metallic components of the ammunition, upon storage for a greater or less length of 1 time, to ta e up mercury from the priming charge and become amalgamated with it. This causes the metal to become more or less brittle and at times this trouble is experienced to such an extent that the metal components of the ammunition crack or fall apart. The use of commercial mercury fulminate in the priming charges of ammunition has proved so troublesome at times in the pastthat attempts have been made to develop priming compounds of the non-fulminate type in order to obviate this difliculty. v v

By means of the recess of this invention I produce mercury ulminate containing substantially no free metallic mercury and this material is used in priming mixtures with all the advantages heretofore ossible with priming mixtures of the nonulminate type and at the same time with the benefit of the use of mercury fulminate which is by far the most satisfactory detonatin ingredient. The mercury fulminate treate according to my process and from which all free mercury has been removed is used in a priming mixture in combination with a suitable oxidizing agent and 4 other well known ingredients of such com ositionsin the usual manner as will be rea ily understood by those skilled in the art.

In carrying out the process and producin the product of my invention I employ ordinary commercial mercury fulminate and heat it to remove any free metallic mercury which ma be present. The time and temperature of eating will vary according to the quality of the mercury fulminate treated. I preferably carry out the heating step under reduced pressure, but this is not essential. By performing the heating step under reduced ressure the time consumed may be considerably shortened. With the usual grade Application filed July 1a, 1923. Serial in. 292,801.

of commercial mercury fulminate now employed b various ammunition manufacturers in t e manufacture of priming compounds I have found that the optimum conditlons comprise a heating period of substantially sixteen hours at a temperature of 140 F. and at a pressure corresponding to four inches of mercury.

The mercury fulminate so treated to remove substantially all of the free metallic mercury .present is then combined with a suitable oxidizing agent and other ingredients of'a primmg mixture and the priming mixture is mixed and charged into primer cups or cartridge cases for rim fire cartridges in a manner well known to those skilled in the art.

By using mercury fulminate substantially free of metallic mercury the amalgamation of the metallic components of the ammunition is greatly diminished, if not entirel 0bv1ated. This amalgamation is primarily, if not entirely, due to the presence of free or elemental mercury in the commercial mercury fulminate ordinarily used in the preparation of prim ln mlxtures. Ammunition loaded with priming mixtures containing mercury fulminate prepared in accordance with my invention w1ll.not shown any appreciable amalgamation even after a considerable time of storage thereby eliminating the most prevalent 'difiiculty and annoyance in the use of mercury fulminate.

Although I have pointed out'above specific values for length of time, temperature and pressure, nevertheless I do not confine myself to these precise figures, nor indeed to the necesslty for reduced pressure inasmuch as these values may be varied to a considerable extent without de arting from the spirit of my invention, w ich is characterized by the use of mercury furminate from which free metallic mercury has been removed. I

I claim:

1. Mercury fulminate which has been freed to a temperature suflicient' toevaporates any free metallic mercury present for a suflicient length of time to eliminate substantiallyiallof such iree mercur i 5 The process of treating mercury fulminate consisting essentially of'subjectmg it to a temperature sufficient .to evaporate any free metallic mercury present for asufiic'ient" length of time to eliminate substantially all 1 of such free mercury and under a liminished pressure. I J 6.

The process of treating mercury ful-- JQ'SEPIiTD. MCNUTT' 

